Why can't I just add anti-freeze?

This is my first winter with an RV. I live in Cleveland Ohio and right now it's 12 degrees. My rig is in an indoor heated storage facility and I didn't winterize. I'm going to Florida in February with stops in Cincinnati, Chattanooga, Tallahassee, and then on to Naples. I'll be returning to Cleveland and cold temperatures again at the end of February.

I haven't drained my water system.

Why can't I just add anti-freeze, and then just flush that out when I get to warmer weather? Then on the way back, just add anti-freeze again?

Why does the system have to be drained first?Thanks for any help that you can provide.Ken

Yup you sure can do it that way.

10 years in the bowels of my MH sitting parked in Wisconsin winters and I have NEVER drained/blown out the water lines in my MH.

Buy 4 to 6 bottles of RV antifreeze, pour into fresh tank, run faucets/toilet till pink, pour down sink drains. Done.

Filling lines with antifreeze from the fresh tank also ensures your water pump is protected too.

When I headed to Florida my rig was already winterized.
I hit the road and de-winterized at a CG when I hit warm weather.

On the way back North I added the antifreeze back in when I hit the colder states. No fuss, no muss do it right at the CG. Walmart sells it for around $3.00 a bottle. Cheap investment for insurance.